a. Field of Invention
This invention pertains to an apparatus for winding elongated strips of material, such as metal strips, into a coil, and more particularly to an apparatus with a core slip member having roller sleeve for eliminating friction with the coil core.
b. Description of the Prior Art
Core slip winding devices are available commercially which, as shown somewhat schematically in FIG. 1, may consist of a rotating drum 2 which supports a plurality of cores 4 and a plurality of axially spaced separators 6. The last separator 6' is positioned against a solid plate 8. A spring 10 cooperates with a knob and screw arrangement 12 and 14 to apply an axial pressure on the cores 4 and separators 6. Separators 6 are keyed (by keying means not shown) to the drum 2 so that the separators and the drums are rotating together. The cores 4 have an inner diameter slightly larger than the outer diameter of drum to allow the cores 4 to slip with respect to the arbor as the drum rotates. This prior art mechanism may be disposed for example down stream of a slitting mechanism which continuously slits a wide sheet into narrow parallel strips 16. The ends of each of these strips 16 are secured to a core 4 so that as the strips 16 come off the slitter, the drum 2 is driven a speed slightly higher than the speed of the slitter allowing the strips to be wound simultaneously into individual coils by the apparatus of FIG. 1. Because the cores 4 are allowed to slip with respect to drum 2, each strip is allowed to wind at its own pace thereby compensating for the difference in thickness between the strips 16. The tension applied to each strip during winding is applied and controlled by the separators 6. One problem with this arrangement is that as more and more strip material 16 is wound on a core 4, the weight and the size of the coil increases thereby increasing the frictional force between the core 4 and the drum 2. As a result, when each coil strips becomes relatively large, especially if the strip 16 is made of a metal, and hence it is heavy, the tension on the strip is affected by the weight of the coil, resulting in an uneven coil.